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Organische Synthesen mit übergangsmetall‐Komplexen, 51. 1‐Metalla‐1,3,5‐triene und 1‐Metalla‐1,3‐dien‐5‐ine von Chrom und Wolfram durch Insertion von Alkinen in MC‐ bzw. CC‐Bindungen von 1‐Metalla‐1,3‐dienen bzw. 1‐Metalla‐1‐en‐2‐inen
Author(s) -
Aumann Rudolf,
Heinen Heinrich,
Hinterding Peter,
Str äter Norbert,
Krebs Bernt
Publication year - 1991
Publication title -
chemische berichte
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.667
H-Index - 136
eISSN - 1099-0682
pISSN - 0009-2940
DOI - 10.1002/cber.19911240541
Subject(s) - chemistry , carbene , alkyne , medicinal chemistry , stereoselectivity , stereochemistry , chromium , catalysis , organic chemistry
Organic Syntheses via Transition Metal Complexes, 51. – 1‐Metalla‐1,3,5‐trienes and 1‐Metalla‐1,3‐dien‐5‐ynes of Chromium and Tungsten by Insertion of Alkynes into MC and CC Bonds of 1‐Metalla‐1,3‐dienes and 1‐Metalla‐1‐en‐3‐ynes, respectively 1‐Metalla‐1,3,5‐trienes L n MC(NEt 2 )–C(Me)C(OEt)–CHCHPh (3,4) and L n MC(OEt)– CHC(NEt 2 ) – C(Me)=CHPh [ 5 , L n MCr(CO) 5 ( a ), W(CO) 5 ( b )] are obtained for the first time from the corresponding 1‐metalla‐1,3‐dienes L n MC(OEt) – CHCHPh ( 1a, b ) under very mild conditions by the insertion of the electron‐rich alkyne Et 2 N–C C – Me ( 2 ) into the MC and the CC bonds, respectively, of 1 . The chelate complex ( 6b ) and the cyclobutenyl carbene complex 7b are isolated as minor side products. 1‐Metalla‐1,3‐dien‐5‐ynes L n MC(NEt 2 ) – C(Me)=C(OEt) – C CPh [ 9, 10 , L n MCr(CO) 5 ( a ), W(CO) 5 ( b )] are formed with high regio‐ and stereoselectivity on insertion of 2 into the MC bonds of 1‐metalla‐1‐en‐3‐ynes 8 . X‐ray data are given for the tungsten complex 3b .